Search Postgresql Archives

Re: Speed of lo_unlink vs. DELETE on BYTEA

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



At 07:43 25/09/2011, Reuven M. Lerner wrote:

Hi, everyone. Daniel Verite <mailto:daniel@xxxxxxxxxxxxxxxx><daniel@xxxxxxxxxxxxxxxx> wrote:

It would thus appear that there's a slight edge for dumping bytea, but nothing super-amazing. Deleting, however, is still much faster with bytea than large objects.

The problem you have is with compression/decompression on large objects. If you see at it's sizes, you get 680KB for large objects and 573MB for bytea. Postgresql needs to decompress them before the dump. Even worse, if your dump is compressed, postgres decompress each large object , dump it and recompress. For this test, switch off compression on large objects/toast. For long term, perhaps a request to postgresql hackers to directly dump the already compressed large objects. The toast maybe more difficult because there are not only big size columns, but any column whose* size is bigger than a threshold (don't remember now, 1-2KB or similar)

* Is it whose the correct word? I hope i have expressed correctly.

EFME


--
Sent via pgsql-general mailing list (pgsql-general@xxxxxxxxxxxxxx)
To make changes to your subscription:
http://www.postgresql.org/mailpref/pgsql-general



[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
[Index of Archives]     [Postgresql Jobs]     [Postgresql Admin]     [Postgresql Performance]     [Linux Clusters]     [PHP Home]     [PHP on Windows]     [Kernel Newbies]     [PHP Classes]     [PHP Books]     [PHP Databases]     [Postgresql & PHP]     [Yosemite]
  Powered by Linux